Apparatus for tracking and recording vital signs and task-related information of a vehicle to identify operating patterns

ABSTRACT

An apparatus is provided for diagnosing the state of health of a vehicle and for providing the operator of the vehicle with a substantially real-time indication of the efficiency of the vehicle in performing an assigned task with respect to a predetermined goal. A processor on-board the vehicle monitors sensors that provide information regarding the state of health of the vehicle and the amount of work the vehicle has done. In response to anomalies in the data from the sensors, the processor records information that describes events leading up to the occurrence of the anomaly for later analysis that can be used to diagnose the cause of the anomaly. The sensors are also used to prompt the operator of the vehicle to operate the vehicle at optimum efficiency.

CROSS REFERENCE TO RELATED APPLICATIONS

This patent application is a divisional of U.S. application Ser. No.11/410,648 filed on Apr. 25, 2006 (Now U.S. Pat. No. 7,765,039), whichis a divisional of U.S. application Ser. No. 10/383,822 filed on Mar. 7,2003 (Now U.S. Pat. No. 7,039,507), which is a continuation of U.S.application Ser. No. 08/448,764 filed on May 24, 1995 (Now U.S. Pat. No.6,546,363), which is a divisional of U.S. application Ser. No.08/196,480 filed on Feb. 15, 1994 (Abandoned).

TECHNICAL FIELD OF THE INVENTION

The invention generally relates to the identification of anomalies inthe operation of a vehicle and, more particularly, to the collection andanalysis of data derived during operation of a vehicle that provides abasis for diagnosing the cause of anomalies in the vehicle's operation.

BACKGROUND OF THE INVENTION

All vehicles today have various sensors for identifying and trackingcritical “vital signs” of a vehicle. In their simplest form, thesesensors include an oil pressure gauge, a water temperature gauge and anelectrical system charging/discharging gauge. In more sophisticatedvehicle systems, these vital signs may be expanded to include thecondition of the brake system, transmission shift indicator, and soforth. In fact, for every component or subassembly of a vehicle, asensor can be adapted for indicating whether that component orsubassembly is operating in a routine or “critical” state—i.e., a statethat if maintained will cause the component or subassembly to fail.

Like the monitoring of vital signs, it is also known to employ sensorson-board a vehicle to track performance of the vehicle. An example ofsuch an on-board system is illustrated in U.S. Pat. No. 4,839,835 toHagenbuch. By sensing and monitoring vehicle parameters related to thetask being performed by a vehicle, a record can be established thatdescribes how effectively the vehicle is performing and provides theoperator of the vehicle with information from which future operations ofthe vehicle can be planned to maximize performance. Task-relatedparameters are parameters such as load carried by a vehicle, grade ofthe road on which the vehicle is operating, loads hauled per hour, tonshauled per hour, and the like. In general, the task-related parametersare those parameters that provide indicia of the work done by thevehicle, where work is proportional to the weight of a vehiclemultiplied by distance it is carried. Production performance of thevehicle is generally evaluated in the amount of work done by the vehiclein a unit of time—e.g., miles per hour, tons per hour and the like.

Today, there are many companies producing equipment for monitoring thestate of health of a vehicle's components and subassemblies—i.e., its“vital signs.” There are also many companies producing vehicleproduction monitoring equipment. However, to the best of applicant'sknowledge, none of these products has integrated vehicle production withvehicle condition. It is expensive to operate all vehicles and, inparticular, large load-carrying vehicles such as trucks. Accordingly, inan effort to improve the up time or operating time of the vehicle, it isvery important to monitor the critical vital signs of a vehicle.However, in addition to simply monitoring these vehicle critical vitalsigns, it is even more important to know what caused a vehicle vitalsign to reach a critical condition that, if continued, will causefailure of a component or subassembly. When taken as disparate items,tracking either vital signs or production parameters gives only apartial picture of a vehicle's operation.

SUMMARY OF THE INVENTION

It is the general object of the invention to diagnose the cause ofanomalies in the values of the state-of-health parameters of a vehicle.

It is a related object of the invention to employ the foregoingdiagnosis to control the operation and use of the vehicle to reduce theseverity and number of anomalies of the values of the state-of-healthparameters of the vehicle, thereby extending the useful life of thevehicle while maintaining production goals.

It is also an important object of the invention to provide a historicalrecord of the values of the condition and performance parameters of avehicle, which can be used to schedule future maintenance andutilization of a vehicle.

It is yet another important object of the invention to provide to theuser of a vehicle real-time information regarding the degree with whichthe vehicle is being utilized—i.e., the maximization of all performanceand condition parameters within their normal ranges. It is a relatedobject of the invention to signal the user of a vehicle whether theutilization of the vehicle at the moment is optimum and to also indicatewhether the user has utilized the vehicle over a known time period(e.g., a work shift) in a manner that meets expectations.

These and other objects and advantages of the present invention, as wellas additional inventive features, will be apparent from the descriptionof the invention provided herein.

Briefly, the invention identifies a poor state of health of a vehicleand provides data regarding the recent use of the vehicle that can beused to effectively diagnose the cause of the poor health. Operating thevehicle beyond its normal operating conditions stresses components andsubassemblies. If stressed to an extreme or for a long period of time,the component or subassembly may fail. On the other hand,under-utilization of the vehicle results in undue operating expenses andinefficient use of the vehicle. Therefore, the invention also provides avisual prompt to the operator of the vehicle on a substantiallyreal-time basis an evaluation of the efficiency of the vehicle'soperation with respect to a predetermined norm for an assigned task.With these two aspects of the invention, the operator of the vehicle isencouraged to operate the vehicle efficiently while at the same timebeing mindful that overstressing the vehicle to make up for a period ofinefficiency will be recorded and noted by the operator's supervisors.

An electronic processor on-board the vehicle acquires vital sign dataand work-related data at predetermined time intervals from sensorsmounted to the vehicle for providing a set of vital sign data and a setof work data. The sensors that provide vital sign data sense parametersof the vehicle's subassemblies and components that are indicative oftheir state of health. The sensors that provide the work data senseparameters that are indicia of the task performed by the vehicle and ofthe amount of work the vehicle has done in performing the task. A memoryis associated with the electronic processor and stores the vital signand work data acquired by the processor in a format that allows the datato be retrieved from the memory in a manner that correlates the vitalsign and work data. The processor includes a device for detecting afailure mode of the vehicle, where the failure mode is a value of one ofthe vehicle's state-of-health parameters that indicates a component orsubassembly of the vehicle is in a poor state of health and failure ofthe component or subassembly is impending. In response to a detection ofthe failure mode, the processor provides indicia in the memory thatidentifies the time the failure occurred and the chronology of thevalues of the production-related data immediately preceding the time thefailure mode occurred. In the illustrated embodiment, the indicia isdata that identifies which one of the vital sign sensors has reached acritical condition and the value of the output signal from the vitalsign sensor that caused detection of the failure mode.

When the failure mode detects a crash of the vehicle, it is particularlydesirable to continue acquiring and storing production-related dataduring the entire crash event. In terms of the sensor readings, it istherefore desirable to provide indicia in the memory for the duration ofthe time period that the vehicle is moving after a crash event has beensensed.

In the illustrated embodiment, the indicia is provided by a memory thatpermanently stores an anomaly of a vital sign sensor with a chronologyof the work-related sensors for a predetermined period of timeimmediately preceding the processors sensing the anomaly in the vitalsign sensor. Other types of indicia can alternatively provide a recordfor later use in diagnosing anomalies in the operation of the vehicle.

In another aspect of the invention, a predetermined number of the mostextreme values of the data sampled from the vital sign sensors arestored in memory for later use in diagnosing a failure mode of theinvention or in planning the future operation of the vehicle.

Finally, the invention provides a substantially real-time analysis ofthe production efficiency of the vehicle and reports to the operator ofthe vehicle whether he is presently below, at or above expectedefficiency. In the illustrated embodiment, the expected efficiency ofthe vehicle is a rate of production norm that assumes operation of thevehicle in a normal mode, meaning operation of the vehicle with fullloads and within the normal ranges of values for the vital signparameters of the vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may best be understood with reference to the accompanyingdrawings wherein an illustrative embodiment is shown and in thefollowing detailed description of the preferred embodiment. Although theillustrated embodiment of the invention is shown in the environment of ahaulage vehicle, the invention is also applicable to passenger vehiclessuch as automobiles, buses and the like. Indeed, any type of vehicle mayincorporate this invention, particularly with respect to diagnosing thecause of a crash event.

FIG. 1A is a perspective view of a haulage vehicle incorporating thediagnostic system of the present invention;

FIG. 1B is the vehicle of FIG. 1A illustrating the location of aplurality of sensors that provide information or indicia from which thework performed by the vehicle can be evaluated in accordance with theinvention;

FIG. 1C is the vehicle of FIG. 1A illustrating the location of aplurality of sensors that provide information regarding the state ofhealth of the vehicle;

FIG. 2A is a schematic block diagram of the hardware architecture of thediagnostic system of the invention, which is incorporated in the vehicleof FIGS. 1A-1C;

FIG. 2B is a functional block diagram of the diagnostic system of theinvention with respect to diagnosing a failure mode of the vehicle;

FIG. 2C is a front view of a control panel for the diagnostic system ofthe invention, which includes a keypad and an LCD display;

FIGS. 3A, 3B and 3C are each state machine diagrams for the diagnosticsystem of FIG. 2A in connection with its diagnosis of the rate ofproduction of the vehicle;

FIG. 4 is a memory map illustrating the format of a memory of thediagnostic system for a data base of production goals used by the statemachine of FIGS. 3A-3C;

FIG. 5A is a memory map illustrating the format of a chronology memoryof the diagnostic system for building a historical data base recordingevents leading up to the detection of a failure mode;

FIG. 5B is a schematic representation of one of the memories in thechronology memory of FIG. 5A;

FIG. 6A is a state machine diagram for the diagnostic system of FIG. 2illustrating the comparison of work-related sensor data with criticalvalues for the vital sign data stored in memory for the purpose ofidentifying a failure mode of the vehicle in accordance with anotheraspect of the vehicle;

FIG. 6B is a memory map illustrating the format of a memory that storesthe historical information accumulated by the chronology memory of FIG.5A upon detection of a failure mode of the vehicle;

FIG. 7A is a state machine diagram for the diagnostic system of FIG. 2illustrating the comparison of the value of the data from a vital signsensor with each of the historical ten most extreme values of the dataof that sensor in order to identify anomalies in the operation of thevehicle;

FIG. 7B is a schematic illustration of a memory stack of the historical10 most extreme values for data from a vital sign sensor and a relatedmemory for storing the chronology values of the production-relatedsensors at the time each extreme value occurred;

FIG. 8 is a map of data available from the diagnostic system of theinvention, the data being accessed through a menu system as illustratedthat employs a keypad and a display;

FIGS. 9A-9C illustrate a flow diagram for navigating through the menumap of FIG. 8 for displaying various diagnostic information held in amemory according to the invention;

FIGS. 10A-10I are flow diagrams for displaying some of the diagnosticinformation stored in memory;

FIGS. 11A-11C are flow diagrams of diagnostic subroutines for diagnosingthe production status of the vehicle on a real-time basis and displayingthe status to the operator of the vehicle in accordance with one aspectof the invention; and

FIGS. 12A and 12B are flow diagrams of diagnostic subroutines foraccumulating a historical data base of vital sign conditions and taskindicia and identifying the data in the historical data base withdetection of a failure mode of the vehicle in accordance with anotheraspect of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning to the drawings, and referring first to FIG. 1A, an exemplaryvehicle 11 incorporates the diagnostic system of the invention andincludes a body 13, which is hinged to the frame 15 of the vehicle attwo complementary hinge assemblies 17, only one of which can be seen. Bycontrolling the extension of telescoping hydraulic cylinders 19 and 21,the truck body 13 is pivoted between a fully inclined or dump positionand a lowered or rest position. One end of each hydraulic cylinder 19and 21 is fastened to a hinge assembly (not shown) located on the bottomof the vehicle body 13. The opposing end of each cylinder 19 and 21 isfastened to an articulation 22 on the frame 15 of the vehicle 11, ofwhich only one can be seen in FIG. 1A. Structurally, the body 13 of thevehicle 11 consists of steel panels 23, which form the shape of thebody, and beams 25 which provide the structural framework of the body.

In silhouette in FIG. 1A is the drive train 27 of the vehicle 11. Thedrive train includes three main subassemblies; namely, the prime moveror engine 28, the transmission 29 and the drive axle 30. In mechanicaldrive trains, the drive axle 30 is mechanically coupled to thetransmission 29 by way of a differential. In an electrical drive train,electric motors are located at each end of the axle 30 and thetransmission 29 is replaced by a generator (not shown) electricallycoupled to the electric motors. Both types of drive trains are wellknown in vehicles such as the vehicle 11.

Often, trucks, such as the vehicle 11 shown in FIG. 1A, are very large.For instance, it is not uncommon for the diameter of one of the tires 26of the vehicle 11 to be as great or greater than the height of anaverage man. Accordingly, the tremendous size of these vehicles makesthem expensive to operate and repair. Since these vehicles representboth a large capital investment and a large operating expense,preventing both overloading of the body 13 and under-utilization of itsload capacity (i.e., underloading) are important considerations inensuring the vehicle is operated in the most profitable manner. Inparticular, if the vehicle 11 is overloaded, it will tend to have ashorter usable life because of the excessive wear caused by theoverloading. On the other hand, if the vehicle 11 is underloaded, thevehicle must be operated over a longer period of time to achieve thesame results that are achieved when the vehicle is fully loaded, therebyconsuming more fuel and wearing the parts of the vehicle to a greaterdegree than necessary. Therefore, the ability to accurately measure theamount of work performed by the vehicle 11 is important to evaluatingand ensuring its efficient operation. Also, since these vehicles areextremely expensive to operate, information regarding performance of thevehicle can be of great economic value since performance-related datacan be used to ensure these expensive vehicles are utilized in theirmost efficient and profitable manner.

Typically, a shovel or front-end loader is used to fill the body 13 ofthe vehicle 11. With a front-end loader (not shown), material is loadedinto the body 13 of the vehicle 11 by a bucket located at the end of anarm of the loader. The body 13 has a weight and volume capacity thatnormally requires the dumping of a plurality of loaded buckets into thebody 13 in order to load the body to its full capacity. Even though theoperator of the front-end loader is at an elevated level when operatingthe loader, he or she may not be in a position to see over the top ofthe body to determine the level of loading. Moreover, the materialloaded into-the body 13 of the vehicle 11 often has varying densities,causing the operator of the loader to guess how much material can besafely loaded without overloading the vehicle. Consequently, it isdifficult to exactly control the amount of material loaded into the body13 so that the vehicle 11 hauls an optimum amount of material.

Recently, it has become increasingly common for heavy-duty vehicles suchas the vehicle 11 in FIG. 1A to include a plurality of sensorsdistributed about the vehicle for the purpose of monitoring certainimportant performance and vital sign parameters. For example, manysystems are available for vehicles such as vehicle 11 that monitor thestate of health of various important subassemblies and components of thedrive train 27. Typically, gauges or lights are mounted to a panel inthe cab 31 of the vehicle 11 in order for the operator of the vehicle tomonitor each of the sensors and be alerted to any critical state the mayeffect the state of the health of the vehicle if not corrected. One suchsystem is an Electronic Monitoring System (EMS) by Caterpillar, Inc. ofPeoria, Ill., which is described in Caterpillar's publication No.SENR2945. Other systems are:

-   -   (1) Detroit Diesel Corporation's Electronic Controls        DDEC—Brochure No. 7SE 414, Canton, Ohio.    -   (2) Allison Transmission—Brochure No. SA2394XX, Indianapolis,        Ind.    -   (3) Eaton Corporation's Tire Pressure Control System.        Systems such as these distribute sensors about the vehicle 11 in        order to monitor the state of health of critical subassemblies        and components. On-board systems that track performance of the        vehicle 11 are also known and have become increasingly popular        in recent years. An example of an on-board performance        evaluation system is the OBDAS Monitoring System, manufactured        by Philippi-Hagenbuch, Inc. of Peoria, Ill. 61604, which        incorporates the invention described in U.S. Pat. No. 4,838,835.

In the vehicle 11 illustrated in FIG. 1C, various sensors monitor vitalsigns of subassemblies and components of the vehicle. In the vehicle 11illustrated in FIG. 1B, sensors monitor parameters related to thevehicle's production—i.e., the work performed by the vehicle 11. Thevehicle 11 in FIGS. 1B and 1C includes the following sensors in keepingwith the invention:

FIG. 1B—Production-related Sensors 67

-   -   1. Engine RPM 67A    -   2. Throttle position 67B    -   3. Engine fuel consumption 67C    -   4. Distance traveled 67D    -   5. Ground speed 67E    -   6. Inclinometer 67F (vertical axis)    -   7. Angle of turn 67G (horizontal axis)    -   8. Steering Wheel 67H    -   9. Status of brake 67I    -   10. Vehicle Direction 67J    -   11. Load sensor 67K    -   12. Dump sensor 67L

FIG. 1C—Vital Signs Sensor 73

-   -   1. Engine oil temperature 73A    -   2. Engine oil pressure 73B    -   3. Engine coolant level 73C    -   4. Engine crankcase pressure 73D    -   5. Engine fuel pressure 73E    -   6. Transmission oil temperature 73F    -   7. Transmission oil level 73G    -   8. Differential oil temperature 73H    -   9. Differential oil level 73I    -   10. Current amperes to drive motor 73J (on electric drive        vehicles only)    -   11. Drive motor temperature 73K (on electric drive vehicles        only)    -   12. Crash 73L    -   13. Tire air pressure 73M

Each of the foregoing vital sign and production-related sensors 73 and67 is a well known sensor that is commercially available. See SensorsMagazine, 1993 Buyer's Guide, Nov. 2, 1992, Vol. 9, No. 12, HelmersPublishing, Inc., Peterborough, N.H. 03458-0874 (ISSN 0746-9462). Withrespect to the load and dump sensors 67K and 67L, the weight of the loadand when it is dumped can be sensed as described in the above-identifiedU.S. Pat. No. 4,839,835 or, alternatively, the weight of the load can besensed by the change in fluid pressure of the hydraulic suspensionsystem of the vehicle 11 such as disclosed in U.S. Pat. Nos. 4,635,739and 4,835,719.

The hardware architecture of the diagnostic system according to theinvention is schematically illustrated in FIG. 2A. A processor 41 of thesystem is of a conventional configuration, including a 16-bitmicroprocessor 43 (a 68HC16 processor by Motorola) and an associatedreal-time clock 40 with battery power backup. An EPROM 45 contains theprogram executed by the microprocessor 43. A RAM 47 stores dynamicinformation collected by the microprocessor 43 under program control inaccordance with the invention. In a conventional manner, interrupts 49,51 and 53 interface the microprocessor with various peripheral devices.Specifically, the interrupt 49 interfaces the microprocessor 43 to aradio transceiver and an associated modem 55 by way of an RS-232 serialport. The interrupt 53 interfaces the microprocessor 43 with a controlhead 57 that includes a keypad 59 and a display 61. From an RS-232serial port in the control head 57, a lap top personal computer 63 canbe coupled to the microprocessor 43 for downloading data contained inthe RAM 47.

An interface 67 controls the transmission of data from the groups ofwork-related sensors 67 to the microprocessor 43 via the interrupt 51and a opto-isolator 69. Similarly, an interface 71 controls thetransmission of analog data from the group of the vital sign sensors 73and the pressure transducers 67K to the microprocessor 43 via ananalog-to-digital converter 75. A printer 77 is connected to themicroprocessor 43 through a parallel port via an opto-isolator 79.Finally, the microprocessor is also coupled to drive load lights onethrough five by way of an opto-isolator 81.

By appropriate programming of the processor 41, the transceiver 55 canprovide for downloading the data held in the RAM 47 as explained morefully hereinafter. The downloading can be done in real time as the dataaccrues or it can be downloaded in response to polling from a basestation. In keeping with the invention, a crash event sensed by theprocessor 41 as explained hereinafter may automatically key thetransceiver 55 to download the data in the RAM 47 and also serve tobroadcast a distress signal, which serves to alert other personnel(e.g., at a central station) that immediate aid may be required.

FIG. 2B is a functional block diagram of the diagnostic system withrespect to one aspect of the invention. As FIG. 2B indicates, theprocessor 41 receives data from both the production-related sensors 67and the vital sign sensors 73. As explained more fully hereinafter, theprocessor 41 periodically samples the data from the production-relatedsensors 67 and stores that data in a memory storage 83 forproduction-related inputs.

Briefly, this memory 83 provides a historical database of sampled datafrom the production-related sensors 67 for the last approximate 606minutes (about ten hours). In response to detection of anomalies in thevalues sampled to the processor 41 from the vital sign sensors 73, theprocessor transfers some or all of the historical data in the memorystorage 83 to diagnostic memories 85, 87 and 89 in FIG. 2B.

In response to detection of a crash of the vehicle 11 from a high valueof the data received from the accelerometer, the processor 41 stores allof the historical data maintained in the memory storage 83 into thediagnostic memory 85. If the processor 41 detects a value of one of thevital sign sensors 73 exceeding a pre-program critical value, theprocessor stores into the diagnostic memory 89 the identity of the vitalsign sensor, the value of its data and a chronology of some or all ofthe production-related data from the historical database in the memorystorage 83. Preferably, the chronology of the production-related datastored into the diagnostic memory 89 is data sampled at approximatelyone second intervals. Finally, the diagnostic memory 87 maintains theten most extreme readings from each of the vital sign sensors 73. Witheach new data sampling of the vital sign sensors 73 by the processor 41,the list of the ten most extreme readings for each of these sensors, isupdated. If a new sampling of the data from a vital sign sensor 73results in an identification of that reading as one of the historicalten highest or lowest readings, the smallest of the values (i.e., theleast extreme) stored in the memory 87, it is deleted and the new valueis entered in its place. Also, the diagnostic memory 87 includes addresslocations for storing a chronology of the work-related sensors 67derived from the memory storage 83 at the time each of the extremevalues was identified. Preferably, the data in the chronology of thework-related values stored in the diagnostic memory 87 are sampled at amaximum rate of once per second.

FIG. 2C is a plan view of the control head 57 of the diagnostic systemaccording to the invention. The control head 57 includes the keypad 59and the display 61. The display 61 is a liquid crystal display (LCD)that provides four lines of text. The keypad 59 includes a shift key 60that provides for each of the other keys to perform two functions,depending on the state of the shift key as is well known in the art ofcomputer-based systems.

In accordance with one important aspect of the invention, the processor41 of the diagnostic system determines an actual rate of production on areal-time basis, compares the actual rate to a pre-programmed goal anddisplays the results of the comparison on the screen of the display 61.To achieve this result, the processor 41 first accumulates in the RAM 47the total weight of the loads hauled by the vehicle 11 during anoperator's shift. The total weight is then divided by the elapsedoperating time of the shift in order to determine a production rate. Thecalculated rate of production is compared with a production goal and theresults of the comparison are periodically displayed to the operator ofthe vehicle 11 on the screen of the display 61, thereby providing theoperator with an evaluation of the vehicle and the operator'sperformance as the operating shift progresses. The value of thepre-programmed production goal is selected to take into account the workarea of the vehicle 11—e.g., the distance between load and dump sites,the difficulty of the route between load and dump sites and the like. Inthe simplest implementation of this feature of the invention implementedby the computer program of the Appendix, a single value for theproduction goal is programmed into the system and stored in memory. In amore sophisticated implementation, a table of production goals iscorrelated with different combinations of load and dump sites, loadingequipment and dump site restrictions.

In executing this aspect of the invention, the processor 41 functions asa sequence of state machines, the most important of which areillustrated in FIGS. 3A, 3B and 3C. In FIG. 3A, the processor 41functions as an accumulator 91 to add the weight of a load that has justbeen dumped, as detected by the dump sensor 67L. Next, in FIG. 3B theprocessor 41 functions as a divider 93 whose numerator input is thetotal weight from the accumulator 91 and whose denominator input is theelapsed time of the operator's shift—i.e, the elapsed operating time.Finally, the actual production rate, which is the output of the divider93, is one of two inputs to the processor 41 configured as a comparator95 in FIG. 3C. The other input is the production goal stored in the RAM47. The results of the comparison is an output from the comparator 95that indicates whether the actual production is below, above or at an“average” production, which is a range of values surrounding the valueof the production goal as explained in connection with the flow diagramsof FIGS. 11A-11C.

As explained more fully in connection with the menu map of FIG. 8, theoperator of the vehicle may enter load and dump site information intothe system by way of the keypad 59. If the vehicle 11 is re-assignedload and/or dump sites during a work shift, the value of the productiongoal may need to be adjusted to take into account differences in the newhaul cycle, the haul cycle being a complete round trip in a work area.In other words, a “haul cycle” is defined as the route of the vehicle 11from a load site, to a dump site and back to a load site or from a dumpsite, to a load site and back to a dump site. A “segment” of a haulcycle is any portion of the haul cycle, such as the route between a loadand dump site and the time of travel or the elapsed time the vehicle 11stays at either site (i.e., loading or dumping plus waiting time).

With the foregoing variability of the haul cycle in mind, the diagnosticsystem includes a memory of production goals such as the memory 97 ofFIG. 4. As suggested by the illustration of the memory 97, itconceptually organizes values of production goals in rows and columns sothat each variation of a haul cycle can be assigned its own value of theproduction goal, which is used by the state machines of the processor 41in FIG. 3. The memory addresses of the rows in FIG. 4 are combinationsof different load sites and loading equipment used in the work area ofthe vehicle. The memory addresses of the columns in FIG. 4 are thecombinations of different dump sites and hopper/crusher equipment. As anexample, FIG. 4 indicates load site B, dump site A, loader equipment No.1 and hopper No. 1 have been entered into the system by way of thekeypad 59 as information identifying the present haul cycle of thevehicle 11. The row and column addresses for this combination of sitesand equipment identifies a value of the production goal at the locationmarked in FIG. 4. It is this value that is provided to the processor 41in FIG. 3C when it is configured as the comparator 95.

In accordance with another important aspect of the invention, thediagnostic system includes a device for detecting a failure mode of thevehicle and capturing a chronology of the values of the productionparameters immediately prior to the occurrence of the failure mode. Thechronology is captured in a memory of the diagnostic system for laterretrieval for the purpose of diagnosing the cause of the failure. Afailure mode is identified when a value of one of the vital signparameters reaches a critical value, that being a value either greaterthan or less than a reference value. The identity of the vital sign andits critical value that caused the failure mode to occur is stored andcorrelated with the captured chronology of the production parameters.

When the state of health of the vehicle 11 reaches a critical conditionas determined by the system in response to the values of the vital signsensors 73, the recent chronology of values read by the system from theproduction-related sensors 67 is stored in the memory 89, which is anumber of address locations in the RAM 47 that preserves the data untilan operator of the system removes it. The production-related parametersthat provide useful chronologic information for diagnosing the cause ofa failure mode are in three categories—i.e., engine, position andrelative speed of the vehicle, and load. When the position, speed andtotal gross weight (i.e., tare weight plus weight of load) of thevehicle 11 are known, the value of the work being done by the vehiclecan be determined. Thus, when vital signs are correlated with productionparameters that define work, the relative efficiency of the vehicle 11in its haul cycles can be monitored and diagnosed.

In keeping with the invention, the following production-relatedparameters exemplify the type of vehicle parameters that are monitored,temporarily stored in a memory and then permanently stored with vitalsign data when a failure mode is detected.

1. Engine

-   -   A. Engine RPM    -   B. Engine throttle position, particularly as it relates to        diesel engines    -   C. Engine fuel consumption relative to work done by the vehicle,        i.e. vehicle ground relative position data        2. Vehicle Ground Relative Position and Speed of the Vehicle    -   A. Drive wheel RPM, speed and distance (speedometer/odometer).        This parameter is useful with respect to a comparison to the        actual ground speed of the vehicle (see item B). Wheel rotation        data that does not correspond to ground speed data indicates        wheel slippage.    -   B. Ground speed or non-driven tire RPM, i.e. a steering tire        typically. The ground speed of the vehicle 11 is particularly        applicable to haulage vehicles and/or vehicles pulling a large        load at speeds that would be considered off-highway speeds,        speeds typically or seldom in excess of 30 MPH.    -   C. Vehicle inclination or vehicle inclinometer. This is the        grade the vehicle 11 is going up or down. Preferably, the        inclinometer 67F in the illustrated embodiment includes both        fore-to-aft and side-to-side data.    -   D. Angle of turn. Is the vehicle turning or going straight        through a compass input? Angle of turn is detected by a compass        and compared with the amount and rate of turn of the steering        wheel. This parameter is particularly useful in connection with        diagnosing a crash of the vehicle 11. In the illustrated        embodiment the angle of turn is detected by a compass 67G.    -   E. Steering wheel angle and rate of turn. Sensing of this        parameter is not implemented by one of the sensors 67 in the        illustrated embodiment, but it may be desirable to include such        a sensor in connection with diagnosing a crash event. The angle        of the steering wheel and the rate of turning it immediately        prior to a crash can complement the values of other parameters        in diagnosing a cause of a crash.    -   E. Vehicle braking. Two types of sensors can be employed for        this parameter. One is a simple on/off status sensor. The other        type of sensor senses the degree of braking by sensing the        pressure of the fluid in the hydraulic brake lines. In the        illustrated embodiment, the brake sensor 67I is preferably of        the second type, which senses the degree of braking. This        information can be particularly useful in connection with        diagnosing a crash condition. For example, if the brakes are        applied, what was the vehicle speed on brake application? What        was the inclination or grade the vehicle on brake application?        What was the grade of the vehicle relative to the distance        traveled with the brakes applied? Over what distance were the        brakes applied, and what was vehicle speed on release or brakes?        As an adjunct to the braking question, what was the vehicle's        total gross weight relative to the braking question? What was        the load on the vehicle relative to the braking capability of        the vehicle on the grade it was being driven on, at the speed it        was being driven, on brake application.    -   G. The status of the operator's seat belt is also a particularly        useful parameter for diagnosing the cause of a crash event        detected by the system. Although not included in the illustrated        embodiment, sensor for sensing this parameter are well known.    -   H. Vehicle direction. In the illustrated embodiment, this        parameter is senses by sensors that sense the position of a        shift lever in the cab 31 of the vehicle. Specifically, a        neutral and reverse sensor 67J sense this parameter in the        vehicle 11.    -   I. Dump of a load. This parameter aids in defining a haul cycle        of the vehicle. In the illustrated embodiment a dump sensor 67L        is mounted to the body 13 of the vehicle 11 in order to sense        the pivoting of the body, which is interpreted as a dump event        by the processor 41.

3. Vehicle Load

-   -   A. Weight sensors such as those in the '835 patent.

In the illustrated embodiments, values for these parameters are providedthe production-related sensors 67. As inputs from the sensors for theproduction-related parameters of the above items 1, 2, and 3 are read,they are recorded in the RAM 47 that is continually updated. The readinginterval for these inputs is a minimum of four times a second, with theamount of data then stored to memory diminishing with time from when thereading was taken. In others words, readings taken most recently are allstored to the memory 83, and readings taken some time ago are graduallydeleted from memory.

As an example of the pattern for retaining data from theproduction-related sensors 67 and vital sign sensors 73, the data thatis stored in the memory 83 at any given instant is as follows:

-   -   A. For the last two minutes of vehicle operation, readings        stored in memory are those taken at four times a second or 480        readings.    -   B. For the last two to six minutes of vehicle operation, the        readings retained are those at the beginning of the second and        half-way through a second, or two readings per second are        retained for a total of 480 readings retained.    -   C. For the last six to 14 minutes of vehicle operation, one        reading per second is retained in the memory 83 or, again, 480        readings.    -   D. For the last 14 to 30 minutes of vehicle operation, one        reading that is taken every two seconds is retained or, again,        480 readings.    -   E. For the last 30 to 62 minutes of vehicle operation, one        reading that is taken every fourth second is retained in the        memory 83 or 480 readings.    -   F. For the last 62 to 126 minutes of vehicle operation, a        reading that is taken every eight seconds is retained in the        memory 83 or 480 readings.    -   G. Over the last 126 to 606 minutes of vehicle operation, one        reading taken every minute is retained in the memory 83 or,        again, 480 readings.

Vehicle default modes which could result in vehicle production workrelated inputs being recorded to the separate default mode memory wouldbe:

-   -   A. Vehicle vital signs reaching a critical state. At that point,        when the processor 41 detects a critical state, it records the        critical state along with data from the production-related        sensors 67 over the most recent “X” amount of time, with this        amount of time being programmed according to the respective        vehicle vital sign.    -   B. Vehicle crash as detected by the on-board vehicle        accelerometer 73L. If a crash of the vehicle 11 is detected,        then readings over the entire 606 minutes of past vehicle        operation are recorded to the memory 85 along with the vehicle        deceleration measurement in gravity units.

These are then the inputs—(1) production-related sensors 67 and (2)defaults inputs, vital sign sensors 73 or crash sensor (accelerometer73L)—that are then correlated to create a system wherein a vehicleoperator/owner can accurately identify the conditions in which thevehicle 11 was being operated that may have resulted in a vehicledefault mode occurring.

At any given moment, the memory of the diagnostic system includes thefollowing:

-   -   I. A chronology of the values of the production-related        parameters as measured by the on-board sensors 67 for the last        approximate 606 minutes.    -   II. The ten extreme (i.e., highest or lowest) values of each        vital sign parameters read by the system from the sensors 73.    -   III. For each of the ten highest or lowest readings in II, a        programmed time period of the most recent values from the        production-related sensors 67 leading up to the highest/lowest        vital sign reading.

When a value of one of the sensors 73 monitoring a vital sign parameterreaches a critical value or state, the system records the critical valuealong with a chronology of the values of the sensors 67 monitoringproduction-related parameters for a predetermined amount of timeimmediately preceding the critical value. The predetermined amount oftime may be different for each vital sign parameter. For example, a hightemperature of the engine coolant may only require that the last tenminutes of performance-related parameters be correlated with thecritical value of the temperature. By way of comparison, a hightemperature of the engine oil may require the last 30 minutes of valuesfrom the production-related parameters in order to effectively diagnosewhether the cause of the high temperature was from overuse of thevehicle 11. In the case of the coolant temperature, it is moresusceptible to fluctuation than the engine oil and, thus, a lesserhistory of the production-related parameters is required for adiagnosis. In the case of a crash as detected by the accelerometer 73Lon-board the vehicle 11, however, the entire 606 minutes of readingsfrom the production-related sensors 67 are stored along with a value ofthe deceleration of the vehicle measured by the accelerometer.

Turning to FIGS. 5A and 5B, the RAM memory 47 of FIG. 2 includes thechronology memory 83 (see FIG. 2B) organized as illustrated. Data fromeach of the production-related sensors 67 is read either a minimum of orapproximately four times a second and stored in a first memory cell 99.Two minutes worth of data is accumulated in the first memory cell99—i.e., 480 data samples for each sensor 67. As the data becomes older,it is less likely to be helpful in diagnosing a failure mode or anextreme reading from one of the vital sign sensors 73. On the otherhand, slow moving trends in the values of the data can be useful in adiagnosis. As the data ages, the chronology memory 83 retains smallerfractions of the originally sampled data. When the data is approximately606 minutes old (as measured by vehicle operation time), it is no longerstored.

To accomplish the foregoing storage scheme for the data from theproduction-related sensor 67 and the vital sign sensors 73, a pluralityof memory cells are cascaded as illustrated in FIG. 5A. As previouslyindicated, the first cell 99 stores each of the original data samplesfrom the sensors, which are sampled at four (4) times a second. In asecond memory cell 101, the oldest data from the first cell 99 is readtwo times a second. A third memory cell 103 reads the oldest data fromthe second cell 101 once a second. A fourth memory cell 105 reads theoldest data from the third cell 103 once every two seconds. A fifthmemory cell 107 reads the oldest data from the fourth cell 105 onceevery four seconds. A sixth memory cell 109 reads the oldest data fromthe fifth cell 107 once every eight seconds. Finally, a seventh memorycell 111 reads the oldest data from the sixth cell 109 once everyminute. As illustrated by FIG. 5B, each of the cells 99-111 employs acirculating pointer 113 that increments through the addresses of thecell to write new data over the oldest data, using well knownprogramming techniques.

In keeping with the invention, the processor 41 is configured as acomparator 115 in FIG. 6A to compare the present value of one of thevital sign sensors 73 and a critical value 116 held in the RAM memory 47that has been selected as being indicative of a poor state of health ofthe vehicle 11 and the component or subassembly monitored by the sensor.In response to the comparison, the processor 41 provides an outputsignal that indicates either that the sensor reading is within anacceptable or normal range or that the reading is at a critical state,which suggests that vehicle 11 is in a failure mode. The comparator 115of FIG. 6A receives data inputs from each of the vital sign sensors 73,including the accelerometer 73L. If a failure mode is detected for anyof the vital sign sensors 73, some or all of the historical data storedin the chronology memory 83 of FIGS. 2B and 5A is captured, correlatedwith the vital sign sensor whose output has reached a critical state andplaced in the memory 89 of FIGS. 2A and 6B for future access by the userof the diagnostic system.

Separate from comparing each reading of the vital sign sensors 73 to acritical value, the processor 41 also determines whether the reading isone of the ten historically extreme readings. This comparison isintended to identify and track anomalies in the status of the state ofhealth of the device monitored by the sensor. With the identification ofeach anomaly, an appropriate portion of the data in the chronologymemory 83 is duplicated in the chronology memory 87 associated with theanomaly recorded as one of the ten greatest extremes. The collection ofthis data can be accessed by the user of the diagnostic system fortaking corrective action (e.g., maintenance or changing driving habits)in order to avoid a failure mode of the vehicle 11. Of course, the datacan also serve to supplement the data recorded by detection of a failuremode for the purpose of diagnosing the cause.

In FIG. 7A, the processor 41 is again configured as a comparator 117 tocompare the present reading from one of the vital sign sensors 73 withthe smallest of the ten extreme values held in the memory 87 in FIGS. 2Band 7B. If the comparison indicates the new reading is a greater extremethan the smallest extreme previously stored in the memory 87A of tenextremes, a write command 119 reads the new reading into the memoryaddress of the old smallest extreme as suggested by FIG. 7B.Chronological data of the performance-related sensors 67 are duplicatedin a set of memory addresses 87B associated with the memory locationinto which the new vital sign reading has been written.

FIG. 8 is a map of the various data screens that can be displayed by thedisplay 61 of the diagnostic system. Each of the menus and its entriescan be accessed by way of keystrokes to the keypad 59. In thisillustrated embodiment of the invention, some of the data available fromthe menu is intended to be generally accessible, whereas theavailability of other data is limited to those who know a password.Also, some of the menu items allow data to be changed or updated, whileother menu items allow data to be displayed but not changed. All of thedata can be sent to the printer 77 for printing. Because of limitationsimposed by the size of the screen of the display 61, some of the menuitems print to the printer 77 information in addition to that visualizedon the display screen.

In keeping with the invention, the data of the menu items in the LEVEL 3DIAGNOSTICS MENU are intended to identify anomalies in the operation ofthe vehicle 11 that aid in the diagnosing of a component or subassemblyfailure mode. The menu items of the LEVEL 3 DIAGNOSTICS MENU areaccessed by way of keystrokes to the keypad 59 as described hereinafterin connection with FIGS. 9A-9C. The data for each of the menu items canbe visualized on a screen of the display 61 or printed to the printer 77as described hereinafter in connection with FIGS. 10A-10I and 12A-12B.The computer program of the Appendix includes menu items 1-12 of theLEVEL 3 DIAGNOSTICS MENU and items 1-32 of the LEVEL 2 SETUP MENU.Moreover, the computer program of Appendix A includes the productionmonitoring and displaying feature of the invention previously explainedin connection with FIGS. 3 and 4. The failure mode diagnostic routine,however, of FIGS. 28 and 5-7 are not part of the computer program ofAppendix A.

In the menu map of FIG. 8, items 13 through 16 of the LEVEL 3DIAGNOSTICS MENU are the information contained in the memories 85, 87and 89 of FIGS. 2B and 5-7. As will be appreciated by those skilled invehicle systems, many components and subassemblies of the vehicle 11have operating parameters that have a range of values that are normaland indicate a satisfying state of health. Often the range of valuesincludes upper and lower limits. Therefore, the memory 87 of FIG. 2B isdivided into two items 15 and 16 in the menu map of FIG. 8. Item 15contains the ten (10) greatest extremes above an upper limit; whereasitem 16 contains the ten (10) greatest extremes below a lower limit.

In the LEVEL 2 SETUP MENU, items 33 through 36 provide some of theadditional critical values 116 of FIG. 6A. As will be readily apparentto those familiar with vehicle sensors of the type disclosed in theillustrated embodiment, additional critical values 116 may be requiredfor programming beyond the four identified in items 33-36.

By accessing items 1-32 of the LEVEL 2 SETUP MENU, certain variablesused by the computer program of the Appendix are input or updated. Forexample, in item 9, a value is entered for an acceptable percentagevariance between the pressure reading from the pressure sensors 67K andan expected zero offset pressure. In a background subroutine notillustrated, the computer program of Appendix A compares the acceptablepercentage variance and the actual variance between the pressure readingfrom each of the pressure sensors 67K and the expected zero offsetpressure. A variance greater than the programmed acceptable variance isstored as an anomaly that can be viewed on the screen of the display 61at item 5 “Leaking Sensor” of the LEVEL 3 DIAGNOSTICS MENU.

In another example of the data available from the diagnostic system ofthe invention, item 28 of the LEVEL 2 SETUP MENU is a maximum elapsedtime allowed for a continuous reading from one of the pressure sensors67K. In a background subroutine not illustrated, the computer program ofAppendix A monitors the value of the reading from each of the pressuresensors 67K to determine if the reading remains unchanged for more thanan amount of time that has been programmed in item 28 of the LEVEL 2SETUP MENU. If the time period is exceeded, the reading is recognized asan anomaly that is placed in the RAM memory 47 for viewing by the userat item 3 of the LEVEL 3 DIAGNOSTICS MENU. In both of the foregoingexamples, the data can be printed to the printer 77 as explained morefully hereinafter.

Although not discussed herein in detail, the computer program ofAppendix A also includes other menus as suggested by the menu map ofFIG. 8. In a MAIN MENU, the vehicle operator can change the operatoridentification, loading point and dump site and several other operatingvariables that may change during normal operation. The MAIN MENU alsoprovides at item 8 for printing to the printer 77 the basic diagnosticdata held in the RAM memory 47. At item 9 of the MAIN MENU, the othermenus can be accessed if the user enters a correct password.

From item 9 of the MAIN MENU, the system enters a LEVEL 1 MENU asillustrated in FIG. 8 and provides a screen at the display 61 of menuitems 1-6. Each of these menu items is a port to other menus assuggested by FIG. 8. Menu items 1, 2 and 3 are freely accessible withoutany additional security passwords. The menus that can be accessed fromitems, 1, 2 and 3 of the LEVEL 1 MENU allow the user to change names inmemory (NAME SETUP MENU), to display results of a self-diagnosticsroutine for the system (DIAGNOSTICS MENU) and to change or updateprogrammable values for certain basic functions (LEVEL 1 SETUP).

Turning now to the flow diagrams and referring first to the flowdiagrams of FIGS. 9A-9C, a number of subroutines are executed by thediagnostic system in accordance with the menu system mapped in FIG. 8.The flow diagram of FIGS. 9A-9C is an exemplary navigation through themenu system that ends in the display of the menu items associated withthe LEVEL 3 DIAGNOSTICS menu, which are the menu items that contain thedata for diagnosing anomalies in the task-related performance parametersof the vehicle (relative to vital signs) in keeping with the invention.

After power has been applied to the diagnostics system when the vehicle11 is turned on in step 121, all variable values of the diagnosticsystem are initialized in step 122. As part of the startup procedure,the date and time is read from the time clock 40 in step 123. If theprinter 77 is enabled as determined in step 124, the previouslyprogrammed values of several variables are identified in a printout fromthe printer as described in step 125. In step 127, the system looks todetermine whether the keypad 59 is enabled. The system prints at theprinter 77 the following printed message at step 129:

OBDAS 6816 VER 0194 -PAD SQ. IN.  80 TRUCK LAST RUN 01/14/94 13:58:12TRUCK STARTED 02/02/94 07:44:12 TIME OFF 21 DAY 17 HRS 46 MIN 44 SECOPERATOR: READY LINE LOADING POINT: 103 MATERIAL: INDUSTRIAL DUMP SITE:NORTH LAND FILL MAINT CATEGORY: RELEASED TO PROD DELAY CATEGORY: NODELAY ********************************************* IN NORMAL TRUCKOPERATION THE ONLY KEYS USED ARE: MENU TO GET TO MAIN MENU ARROW DOWNMOVE DOWN ONE LINE ARROW UP MOVE UP ONE LINE ENTER SELECT CURRENT LINEESCAPE RETURN TO PREVIOUS SCREENFrom steps 127 or 129, the system returns to step 126 where the valuesof all of the various digital and analog devices are read.

After the start sequence of FIG. 9A has been completed, the systemdisplays a “normal operating screen” at step 128 in FIG. 9B. The screenof the display 61 contains four (4) lines of text. An example of thenormal operating screen is as follows:

08:00:04 02/05/94 PAYLOAD: 50.0 OPER: JIM SMITH (Line 4 scrolls thefollowing information) LOADING POINT: PIT ONE MATERIAL: SHOT ROCKDUMPSITE: CRUSHER TWO MAINTENANCE CATEGORY: RELEASED TO PROD DELAYCATEGORY: NO DELAYLine 1 of the foregoing sample displays the present time and date. Line2 displays the weight of the present payload. Line 3 displays theidentity of the current vehicle operator. Line 4 scrolls across thescreen information regarding the designated loading point, the materialto be loaded, the designated dump site, the maintenance category and thedelay category. In the example, the maintenance category is identifiedas “RELEASED TO PROD,” which means that the vehicle is released for usein ordinary production. The DELAY CATEGORY is a data field to identifyreasons for any delay of the vehicle in normal operation such as loadingequipment being broke down. This applies to any delay other thanmaintenance requirements such as, for example, a flat tire that must berepaired.

From the normal operating screen, the menu system described inconnection with FIG. 8 can be accessed by pressing the “MENU” key.Pressing the “ESCAPE” key returns the display 61 to its normal operatingmode as described above. In response to a keystroke to the MENU key thedisplay 61 will list the first three (3) items in the MAIN MENU. Sincethe screen of the display 61 has only four (4) lines, to see the entireMAIN menu, it is necessary to use the arrow keys (i.e., ↑ and ↓) toscroll the display 61. A cursor 130 (see FIG. 9B at step 134) iscontrolled by the arrow keys to indicate the current item that can beselected by a keystroke to the “ENTER” key. In the drawings, the cursoris illustrated as a series of three asterisks (i.e., ***). Preferably,the position of the cursor is indicated by a flashing icon in aconventional manner. To exit the MAIN MENU, a simple keystroke to the“ESCAPE” key is all that is necessary. In general, a keystroke to the“ESCAPE” key will always take the user back to the previous screen ofthe display 61. Repeated keystrokes to the “ESCAPE” key will eventuallyreturn the system to display the normal operating screen.

Returning to the flow diagram of FIG. 9B, from the normal operatingscreen in step 128, a keystroke to the MENU key in step 139 changes thedisplay 61 from the normal screen to a MAIN MENU screen display in step132. In step 134, the first three (3) entries in the MAIN MENU areinitially displayed. The remaining items in the MAIN MENU are viewed byscrolling the screen using the arrow keys to move the cursor 130 to thedesired item in the MAIN MENU as set forth in step 135.

Once the cursor 130 has been moved to the desired menu item and theENTER key has been pressed, the display 61 may prompt the user to entera password. For example, in the flow diagram of FIG. 9B, the asterisks(***) in step 134 indicate that the cursor 130 has been moved to themenu item identified as LEVEL 1 MENU. As indicated in the menu map ofFIG. 8, access to the LEVEL 1 MENU requires entry of a password. In theflow diagram of FIG. 9B, step 135 assumes that the LEVEL 1 MENU has beenselected by a keystroke to the ENTER key.

In step 137, the user of the system enters a password by way ofkeystrokes to the keypad 59, which is completed by pressing the ENTERkey. In step 139, if the password is one that is recognized by thesystem, the display then changes to a display of the first three entriesof the LEVEL 1 MENU. Otherwise, the display screen continues to promptthe user to enter a correct password (the screen of the display 61 is“Password: XXXXXXX”).

From the LEVEL 1 MENU displayed in step 141, the user of the system usesthe arrow keys to move the cursor 130 to the desired menu item. When thecursor 130 is adjacent the desired menu item, a keystroke to the ENTERkey selects that item as generally indicated by steps 143 and 145. Likeitems on the MAIN MENU, some of the items in the LEVEL 1 MENU requireentry of a password before the system will allow access to the user. Assuggested by the menu map of FIG. 8, the LEVEL 2 SETUP and the LEVEL 3DIAGNOSTICS in the LEVEL 1 MENU both require entry of a password beforethe user can gain access to these menu items. After the cursor 130 hasbeen moved to the desired item or function (e.g., the LEVEL 3DIAGNOSTICS in step 145), the system prompts the system user to enter apassword in step 147. In step 147, the user inputs the password andpresses the ENTER key. If the password is correct in step 151, theselected menu item is displayed in step 153. If the password isincorrect, the screen displays “PASSWORD: XXXXXXX”.

In the example illustrated in the flow diagram of FIG. 9C, the selectedmenu item from the LEVEL 1 MENU is the LEVEL 3 DIAGNOSTICS. In step 153,the menu listing of the items available in the LEVEL 3 DIAGNOSTICS MENUis displayed for selection by the user. In step 155, the user moves thecursor by way of keystrokes to the arrow keys in order to select thedesired menu item. In step 157, the following menu items are availablefor display:

LEVEL 3 DIAGS 1 HIGHEST PAYLOADS 2 HIGHEST SPIKES 3 STUCK TRANSDUCER 4BODY EMPTY PSI 5 LEAKING SENSOR 6 LAST 5 NEUTRALS 7 LAST 5 REVERSES 8LAST 5 DUMPS 9 OBDAS SERIAL # 10 OBDAS PART # 11 CLEAR DIAGNOSTICS 12LEVEL 3 PASSWORD 13 VITAL SIGNS 14 VEHICLE CRASH 15 10 HIGHEST VITALSIGNS 16 10 LOWEST VITAL SIGNSThis menu, like all the other menus, actually displays only four (4) ofthe items at a time since the display 61 in the illustrated embodimenthas only four lines of text available. Each of the sixteen itemsidentified in the above example of the LEVEL 3 DIAGNOSTICS MENU providesdiagnostic data to the display 61 when it is selected by the user bymoving the cursor 130 to a position adjacent the item as describedpreviously in connection with the selection of other menu items.

In step 157, each of the subroutines for the menu items identified inthe LEVEL 3 DIAGNOSTICS MENU may be executed. As previously mentioned,the user can exit this menu and retrace his/her way through the menu mapby keystrokes to the ESCAPE key as suggested by step 159. The followingis a brief description of the diagnostic data available from each of theitems 1-9 and 11 in the example given above of the LEVEL 3 DIAGNOSTICSMENU with reference to the flow diagrams in FIGS. 10A-10I. Items 13through 16 are described in connection with the flow diagrams of FIGS.12A and 12B.

FIG. 10A—Highest Payloads

The screen for this menu item shows the ten highest payloads and thedate of the payload. In FIG. 10A, step 161, the LEVEL 3 DIAGNOSTICS MENUis displayed. Placing the cursor 130 adjacent the item identified asHIGHEST PAYLOADS, and pressing the ENTER key in step 163 causes the tenhighest payloads and the dates of the payloads to be displayed at step165. The information is scrolled over the screen of the display 61 bymoving the cursor 130 in step 167.

The following is an example of the screen:

LOAD DATE 1 80.0 02/05/94 2 73.0 02/07/94 3 81.2 02/08/94

To print the data to the printer 77 in step 171, step 169 requires theF3 key be pressed. The printed data includes additional information suchas the name of the operator and the time of day when the highest payloadwas recorded.

Printing this information at step 171 outputs the payloads, theoperator, and the pressures of the pressure sensors 67K for thatpayload. A sample of the printed report is reproduced below.

***TEN HIGHEST PAYLOADS*** 1. 02/05/94 08:13 80.0 TONS OPERATOR: JIMSMITH PRESSURES: 223.6 230.9 229.5 227.9 2. 02/05/94 08:25 80.0 TONSOPERATOR: JEFF JONES PRESSURES: 231.2 232.1 228.7 230.6

FIG. 10B—Highest Spikes

The screen of this menu item lists the ten highest haulroad spikes alongwith the number of the pressure sensor in which the spike occurred andthe date of the spike.

From the screen of the LEVEL 3 DIAGNOSTICS MENU in step 173, the user ofthe system moves the cursor 130 in step 175 to select item 2 in themenu, which is the HIGHEST SPIKES SUBROUTINE. In response to a keystroketo the ENTER key in step 175, the system moves to step 177 and displayson the screen of the display 61 the first four of the ten highestspikes. By using the arrow keys in step 179, the remaining six spikescan be scrolled into view.

An example of the display screen is as follows:

PAD PSI DATE 1 3 270.0 02/05/94 2 4 258.6 02/05/94 3 1 253.9 02/05/94

In step 183, a keystroke to the F3 key will print at step 181 the topten spikes with date, time, PSI and operator data.

FIG. 10C—Stuck Transducer

The screen of this menu item displays the number of times eachtransducer of the pressure sensors 67 K has been stuck along with thepressure (psi) at which the transducer was stuck and the date of thefirst time it was stuck. This subroutine identifies whether a transduceris stuck (i.e., has been over-pressured to the point it will not returnto its normal zero-load signal). As explained more fully hereinafter, ifthe pressure signal from one of the transducers is expected to be thezero offset output signal, then after a set number of seconds of a highreading after the vehicle body has dumped, the system considers thepressure transducer is stuck at a point above the offset previouslyrecorded for the empty body condition.

At item 28 of the LEVEL 2 SETUP MENU, a pressure has been programmed ora transducer output signal has been programmed as a critical conditionthat must be exceeded for this stuck delay condition to be recorded.

By selecting item 3 of the LEVEL 3 DIAGNOSTICS MENU in steps 185 and189, the screen of the display 61 changes to the first four values ofthe STUCK TRANSDUCER SUBROUTINE. The screen can be scrolled in step 191to view all of the data.

The screen of the display 61 for this menu item is very similar to thehighest payload and spike subroutines of FIGS. 10A and 10B,respectively, in that it will display the number of the pressure sensorand its associated transducer, the pressure at which the transducer isstuck (psi), the number of times the stuck condition has occurred andthe date the first stuck condition occurred. The following is anexample.

PAD PSI FREQ. DATE 1 267.9 1 02/04/94 2 267.2 1 02/04/94 3 264.3 102/05/95

Printing this information to the printer 77 in steps 193 and 195 willoutput this data along with the name of the operator who was drivingwhen the first stuck condition occurred. A sample of the printed reportis as follows:

PAD #1 OPER: JIM SMITH INDICATED 1 TIMES PAD #2 OPER: JIM SMITHINDICATED 1 TIMES PAD #3 OPER: JIM SMITH INDICATED 1 TIMES

FIG. 10D—Body Empty (PSI)

The display screen for this menu item shows the last ten pressurereadings for an empty body condition, along with the date of thereadings. The first reading is the most recent. A new reading isrecorded after each dump. Printing this information out will also givetime and operator data.

From the LEVEL 3 DIAGNOSTICS MENU in step 197, the cursor 130 is movedby the arrow keys at step 201 to select item 4, the BODY EMPTY PSISUBROUTINE. The first four readings are displayed on the screen of thedisplay 61 at step 199 and the remaining readings can be scrolled intoview by using the arrow keys in step 203.

Unless there is a haulback condition (i.e., material retained in thedump body after a dump) or something else that has added material to thebody, this empty body condition should not vary. If it does vary, it isindicative of a problem with the load sensors. By looking at the changein time of the empty body pressure readings, a leaking load sensor canbe diagnosed and the time it first began to leak can be identified. Thefollowing is an example of the data appearing on the screen of thedisplay 61.

PSI 1 01/14/94 #1: 46.5 #3: 6.6 #2: 19.2 #4: 46.3

In steps 205 and 207 printing the data in this menu item to the printer77 includes the screen data with a date, time and operator name. Asample of the printed. report is as follows:

1. 01/14/94 13:57:54 OPER: JIM SMITH PAD #1: 46.5 PAD #3: 6.6 PAD #2:19.2 PAD #4 46.3 2. 01/14/94 13:56:14 OPER: JIM SMITH PAD #1: 34.8 PAD#3 1.5 PAD #2: 13.7 PAD #4 35.6

FIG. 10E—Leaking Sensor

The screen for this menu item shows leaking sensor data for each of thepressure sensors. The screen identifies whether there are any leakingsensors and the date and time the sensors first began to leak. Thefollowing is an example of a screen for this menu item.

1. 02/05/94 10:55:54 2.2 PSI

Whenever the vehicle is turned on, the diagnostic system checks the loadsensors for leaks, provided the vehicle is in neutral and the body 13 isdown as indicated by a low dump signal from the dump sensor.

Thereafter, a reading of the dump sensor 67L is taken after the body 13is lowered and the vehicle is shifted into forward.

When this menu item is selected by way of a keystroke to the ENTER keyin steps 209 and 213, the screen on the display 61 displays a list ofthe pressure sensors 67K as illustrated in step 211 of FIG. 10E. Usingthe arrow keys to move the cursor 130, the user selects one of thesensors in the list and again presses the ENTER key at step 217, whichcauses the display to change to the screen of step 215. This screenshows when the pressure of the selected sensor dropped below theprogrammed value for the offset zero pressure after a dump. The pressureis recorded in an address location of the RAM memory 47 when it dropsbelow the programmed percentage. The percentage is programmed in theLEVEL 2 SETUP MENU (see FIG. 8).

Printing the information outputs the leaking sensor data for theselected one of the sensors 67K plus additional information availablefrom the system's memory. A sample of the printed report is as follows:

SENSOR # 1 02/05/94 12:16:04 OPER: JIM SMITH PRESSURE READING: 2.2 PSI

FIG. 10F—Last 5 Neutrals

Selection of this menu item displays the five most recent shifts intoneutral. The date, time, payload and operator are also displayed.Working from the LEVEL 3 DIAGNOSTICS MENU in step 223, the screen of thedisplay 61 changes in steps 227 and 225 to show when the last fiveneutrals occurred, the date, the time, the operator and the amount ofthe payload.

This is one method of verifying signal integrity of the neutral signal.If neutrals suddenly stopped at a certain point in time, then going backto that point in time determines what may have caused those neutralsignals to stop—e.g., whether a wire was disconnected, a componentfailed or the like.

An example of the screen for this menu item is shown below.

02/05/94 10:50:22 OPER: JIM SMITH WEIGHT: 84.4 TONSA sample of the printed report produced by step 231 in response to akeystroke to the F3 key in step 233 of FIG. 10F is as follows:

1. 02/05/94 10:55:54 78.5 TONS OPER: JIM SMITH 2. 02/05/94 10:50:22 84.4TONS OPER: JIM SMITH 3. 02/05/94 10:48:10 40.4 TONS OPER: JIM SMITH

FIG. 10G—Last 5 Reverses

The screen of this menu item displays the five most recent shifts intoreverse. In steps 235 and 237, this menu item is selected from thescreen of the LEVEL 3 DIAGNOSTICS MENU by moving the cursor 130 to item7, which is the LAST FIVE REVERSES SUBROUTINE. In step 239 the date,time, payload and operator are displayed on the screen to identify theevent. The following is an example of a screen.

02/05/94 11:10:45 OPER: JIM SMITH WEIGHT: 78.5 TONS

By using the arrow keys in step 241, all of the data can be scrolledinto view on the screen of the display 61.

A sample of the printed report from steps 243 and 245 is as follows:

1. 02/05/94 11:10:45 78.5 TONS OPER: JIM SMITH 2. 02/05/94 10:58:21 75.3TONS OPER: JIM SMITH 3. 02/05/94 10:50:17 80.2 TONS

FIG. 10H—Last 5 Dumps

The screen of this menu item displays the five most recent dump eventsin step 249. The date, time, payload and operator are also displayed instep 249.

From the screen of the LEVEL 3 DIAGNOSTICS MENU in step 247, the usermoves the cursor 130 in step 251 to select item 8, which is the LASTFIVE DUMPS SUBROUTINE. In step 253, the data is scrolled into view usingthe arrow keys.

The following is an example of a screen.

LAST DUMP: 1 02/05/94 11:03,28 OPER: JIM SMITH WEIGHT: 79.8 TONS

A sample of the printed report produced in step 255 and 257 is asfollows:

1. 02/05/94 11:03:29 79.8 TONS OPER: JIM SMITH 2. 02/05/94 10:48.37 78.4TONS OPER: JIM SMITH

FIG. 10I—Clear Diagnostics

This menu item clears the memory locations storing the data displayed byitems 1-8. If they are not cleared, new data overwrites old data as itoccurs.

After the CLEAR DIAGNOSTICS MENU item has been selected in steps 259 and263, a warning message is displayed in step 261, which prompts the userto either proceed with clearing the diagnostics or manually escape toavoid loss of data. In step 265, a second keystroke to the ENTER keymoves the system to step 267 where all the diagnostics data is clearedfrom the system memory. Otherwise, the user can avoid erasing thediagnostic data by pressing the ESCAPE key in step 269.

Finally, menu items 9, 10 and 12, when accessed in the LEVEL 3DIAGNOSTICS MENU, display the serial number of the diagnostic system,various part numbers and the password for the menu, respectively. Inselecting the menu item for the password, the user can update or changethe password for accessing this menu. Items 13-16 are discussed below inconnection with FIGS. 12A and 12B.

The production monitoring feature of the invention described previouslyin connection with FIGS. 2-4, is implemented by the computer program ofAppendix A in accordance with the flow diagrams of FIGS. 11A-11C. Eachtime the vehicle 11 has completed a haul cycle (i.e., has dumped aload), the weight of the load is added to a running total weight of allloads hauled by the operator during his shift, which is also called the“elapsed operating time.” In the flow diagram of FIG. 11A, thediagnostic system updates the accumulated total weight hauled by thevehicle 11 when a load has been dumped and re-calculates the rate ofproduction for the vehicle and stores the results of a comparisonbetween the calculated value and a production goal that has beenprogrammed into the system by way of item 17 in the LEVEL 2 SETUP MENU(see FIG. 8). In FIG. 11B, the diagnostic system initializes the“elapsed operating time” when the operator changes. The normal operatingscreen of the display 61 is replaced by a production message at regulartime intervals in FIG. 11C. The production message reads from the datastored in memory in the flow diagram of FIG. 11A whether the presentproduction is “ABOVE PRODUCTION,” “AVERAGE PRODUCTION” or “BELOWPRODUCTION.”

In step 271 of the flow diagram of FIG. 11A, the computer program ofAppendix A determines whether a haul cycle has ended. In making thisdetermination, the processor 41 of FIG. 2 senses a change in the datafrom the dump sensor 67L, indicating that the body 13 of the vehicle 11has been pivoted for the purpose of dumping a load. Alternatively, othersensor readings indicating a dump event can also be used to execute thedecision in step 271. For example, the processor 41 may respond to achange in the data from the transducers of the pressure sensors 67K,which indicate that the body 13 has been lifted off the frame (see U.S.Pat. No. '835). The weight of the load that has just been dumped isdetermined by the processor 41 from the readings of the transducers asdescribed in detail in the '835 patent.

In step 273, the weight of the load is added to a running total oraccumulated weight of all the loads that have been dumped by theoperator during the “elapsed operating time.” With the new value for theaccumulated weight determined in step 273, the diagnostic system of theinvention moves to step 275 where a new rate of production is calculatedfrom the updated accumulated weight and the value of the elapsed time,which is a relative time initiated by the flow diagram in FIG. 11B.

From step 275, the system moves to decision step 277 in order to comparethe actual rate of production to a production goal. If the actual rateof production is greater than the production goal, the system moves todecision step 279. On the other hand, if the rate of production is lessthan the production goal, the system moves to step 281. In both steps279 and 281, the system determines whether the percentage differencebetween the actual rate of production and the production goal is greaterthan a programmed percentage. The programmed percentage is a value thathas been entered into the memory of the system by way of item 17 of theLEVEL 2 SETUP memory shown in FIG. 8. If the percentage difference isless than the programmed percentage, the message “AVERAGE PRODUCTION” isstored in a display area of the RAM memory 47 in step 285. If thepercentage difference between the actual rate of production and theproduction goal is greater than the programmed percentage in step 281,the message sent to the display area of the RAM memory 47 is “BELOWPRODUCTION” as indicated in step 287. If the difference is determined tobe greater than the programmed percentage in step 279, however, thesystem stores in step 283 the message “ABOVE PRODUCTION.” After thedisplay area of the RAM memory 47 has been updated in one of steps 283,285 or 287, the system returns to performing other tasks until the endof the next haul cycle is sensed at step 271.

In the flow diagram of 11B, the system interrogates a memory location ofthe RAM 47 that records the identification of the vehicle operator inorder to determine if the identification has changed. If theidentification is different as determined by the system in step 289, anew operator has control of the vehicle 11 and in step 291, the “elapsedoperating time” is reset. Also, the value of the accumulated weight isreset.

In FIG. 11C, step 293 determines if a time ΔT has elapsed since the lastdisplay of the production message on the screen of the display 61. Ifthe time ΔT has elapsed as determined in step 293, the productionmessage is delivered to the display 61 for a predetermined amount oftime in step 295. From the perspective of the vehicle operator, thefirst line of the screen of the display 61 alternates between the normaloperating screen previously described and the rate of production messagewith the duration of the production message and the time intervalbetween consecutive displays of the message programmed as desired. Thefrequency of the production message, however, should be sufficient tokeep the operator of the vehicle 11 advised as to the current status ofthe vehicle's rate of production with respect to the programmed goal. Inthis manner, if the vehicle 11 is below or above the programmed goal,the operator of the vehicle can take appropriate action in order toensure the vehicle is operated efficiently and profitably withoutrisking unnecessary wear or damage to it.

In keeping with the invention, the chronology memory 83 of FIG. 5A isupdated and maintained by the processor 41 by reading the data from thework-related sensors 67 at regular intervals. In this illustratedembodiment of the invention, the processor 41 reads all the work-relatedsensors 67 at step 311 of the flow diagram of FIG. 12A four times asecond. In step 313, the data read from sensors 67 are transferred bythe processor 41 to the first memory cell 99 (see FIG. 5A) of thechronology memory 83. After the processor 41 has scanned all of thework-related sensors 67, the pointer 113 in FIG. 5B is incremented to anext storage location so that the next scan will read the new data fromthe work-related sensors into the location of the memory 99 presentlycontaining the oldest data. As part of steps 311 and 313 in FIG. 12A,the processor 41 also reads data from one of the memory cells and writesit to another in accordance with the diagram and accompanyingexplanation of FIG. 5A. After the samples have been taken and thechronology memory 83 updated, the processor 41 returns to other tasks.

In FIG. 12B the processor 41 monitors the vital sign sensors 73 foranomalies in the value of their data and reports the anomalies byrecording the anomaly in a memory location in association with achronology of the work-related data leading up to anomaly. In step 297,the processor delivers each data sample from a vital sign sensor to aseries of comparisons with pre-programmed data as set forth in steps299, 301 and 303. If any of these comparisons indicates the value of thedata to be an anomaly, the processor 41 stores the identity of thesensor 73, the anomalous value of the data and an appropriate chronologyof the work-related data that immediately preceded the sampling of thevital sign data.

Specifically, in step 299 of FIG. 12B, the processor 41 determineswhether the value of the data from the vital sign sensor 73 exceeds apre-programmed critical value 116. If the sampled data exceeds thecritical value 116, the identity of the sensor 73, the value of the dataand a chronology of the work-related data is stored in the memory 89 atstep 305. On the other hand, if the data does not exceed thepre-programmed critical value 116, the processor 41 goes to step 301 anddetermines if the value of the data sample is one of the historical tenmost extreme readings. If it is one of the most ten most extremereadings, the processor 41 executes step 307, which stores the value ofthe data sample with the chronology of the work-related data in thememory 87. Finally, if the sampled data is neither exceeding apre-programmed critical value nor one of the ten most extreme values forthe vital sign sensor, step 303 determines whether the sampled dataindicates a crash of the vehicle has occurred. In the illustratedembodiment, the system recognizes a crash when the value of the datasampled from the accelerometer 73L exceeds a pre-programmed criticalvalue 116. If the processor determines at step 303 that a crash hasoccurred, it stores all of the data in the chronology memory 83 in aseparate memory 85 and associates the chronology data with the sensorreading indicating a vehicle crash condition at step 309.

Finally, in connection with steps 299 and 303, the inventioncontemplates continuing to gather data and store the data to thememories 85 and 89 so long as the value of the vital sign parameterexceeds the critical value 116. For example, when the value of theaccelerometer 73L exceeds its critical value 116, the processor 41begins to transfer data from the chronology memory 83 to the memory 85.The processor 41 continues to update the memory 83 and transfer theupdated data to the memory 85 for as long as the data from theaccelerometer exceeds a threshold value. The threshold value may be lessthan the critical value 116. In the example of the accelerometer 73L,the threshold level may be a zero value since all data that is collectedduring a crash may be useful in diagnosing the cause. Thus, data wouldcontinue to be transferred to the memory 85 until the vehicle cam to astandstill (i.e., the data from the accelerometer 73L goes to zero).

All of the references including patents, patent applications andliterature cited herein are hereby incorporated in their entireties byreference.

While this invention has been described with an emphasis upon preferredembodiments, it will be obvious to those of ordinary skill in the artthat variations of the preferred embodiments may be used and that it isintended that the invention may be practiced otherwise than asspecifically described herein. Accordingly, this invention includes allmodifications encompassed within the spirit and scope of the inventionas defined by the following claims.

1. A method for recording operation of a vehicle, the method comprising:monitoring production-related parameters of the vehicle, including aground speed of the vehicle, a position of a throttle for an engine ofthe vehicle and a degree of braking of the vehicle; monitoring vitalsign parameters of the vehicle, including information indicative of achange in the velocity of the vehicle; detecting a collision of thevehicle in response to a sudden change in the velocity of the vehicle;automatically sending a wireless distress signal from the vehicle inresponse to detecting the collision; and capturing theproduction-related parameters of the vehicle before detection of thecollision and the vital sign parameters after detection of thecollision.
 2. The method of claim 1 wherein the production-relatedparameters include an RPM of the engine.
 3. The method of claim 1wherein the production-related parameters include actions of a steeringwheel.
 4. The method of claim 1 wherein the production-relatedparameters include a load on the engine.
 5. The method of claim 1wherein the vital sign parameters include an acceleration of thevehicle.
 6. The method of claim 1 wherein the production-relatedparameters include an on/off status of a braking system of the vehicle.7. The method of claim 1 wherein the production-related parametersinclude a status of a seat belt.
 8. The method of claim 1 wherein theinformation indicative of the change in velocity is a sequence of speedmeasurements taken at known time intervals.
 9. An apparatus forrecording operation of a vehicle, the apparatus comprising: sensors formonitoring production-related parameters of the vehicle, where theparameters include ground speed of the vehicle, a position of a throttlefor an engine of the vehicle and a degree of braking by a braking systemof the vehicle; a first memory for capturing information from one ormore of the sensors for monitoring production-related parameters; asecond memory for receiving the information from the first memory;sensors for monitoring vital signs of the vehicle, where the vital signsinclude a collision of the vehicle; a processor in communication withthe production-related and vital sign sensors and the first and secondmemories for transferring into the second memory the informationcaptured by the first memory in response to detection of the collisionof the vehicle, where the information includes data from one or more ofthe production-related parameters before detection of the collision anddata from one or more of the vital signs sensors after detection of thecollision; and a transmitter for automatically transmitting a distresssignal in response to detection of the collision of the vehicle.
 10. Theapparatus of claim 9 wherein the second memory is a permanent memory.11. The apparatus of claim 9 wherein one of the vital signs sensors isan accelerometer.
 12. The apparatus of claim 9 wherein the informationindicates a change in the speed of the vehicle both before and afterdetection of the collision.
 13. The apparatus of claim 9 wherein thesensors for monitoring production-related parameters includes a sensorfor detecting an on/off status of the braking system.
 14. The apparatusof claim 9 wherein the information includes one or more positions of thethrottle leading up to the detection of the collision.
 15. The apparatusof claim 9 wherein the information includes the degree of brakingleading up to the detection of the collision.
 16. The apparatus of claim15 wherein the information includes one or more positions of thethrottle leading up to detection of the collision.
 17. The apparatus ofclaim 9 wherein the sensors for monitoring production-related parametersof the vehicle include a sensor for determining a state of a seat beltin the vehicle.
 18. A method for recording operation of a vehicle, themethod comprising: monitoring production-related parameters of thevehicle, including a ground speed of the vehicle, a position of athrottle for an engine of the vehicle and an on/off status of a brakingsystem of the vehicle; monitoring vital sign parameters of the vehicle,including information indicative of a change in the velocity of thevehicle; detecting a collision of the vehicle in response to a suddenchange in the velocity of the vehicle; automatically sending a wirelessdistress signal from the vehicle in response to detecting the collision;and capturing the production-related parameters of the vehicle beforedetection of the collision and the vital sign parameters after detectionof the collision.
 19. The method of claim 18 wherein theproduction-related parameters include an RPM of the engine.
 20. Themethod of claim 18 wherein the production-related parameters includeactions of a steering wheel.
 21. The method of claim 18 wherein theproduction-related parameters include a load on the engine.
 22. Themethod of claim 18 wherein the vital sign parameters includes anacceleration of the vehicle.
 23. The method of claim 18 wherein theproduction-related parameters include a degree of braking of the brakingsystem of the vehicle.
 24. The method of claim 18 wherein theproduction-related parameters include a status of a seat belt.
 25. Themethod of claim 18 wherein the information indicative of the change invelocity is a sequence of speed measurements taken at known timeintervals.
 26. An apparatus for recording operation of a vehicle, theapparatus comprising: sensors for monitoring production-relatedparameters of the vehicle, where the parameters include ground speed ofthe vehicle, a position of a throttle for an engine of the vehicle andan on/off status of a braking system of the vehicle; a first memory forcapturing information from one or more of the sensors for monitoringproduction-related parameters; a second memory for receiving theinformation from the first memory; sensors for monitoring vital signs ofthe vehicle, where the vital signs include a collision of the vehicle; aprocessor in communication with the production-related and vital signsensors and the first and second memories for transferring into thesecond memory the information captured by the first memory in responseto detection of the collision of the vehicle, where the informationincludes data from one or more of the production-related parametersbefore detection of the collision and data from one or more of the vitalsigns sensors after detection of the collision; and a transmitter forautomatically transmitting a distress signal in response to detection ofthe collision of the vehicle.
 27. The apparatus of claim 26 wherein thesecond memory is a permanent memory.
 28. The apparatus of claim 26wherein one of the vital signs sensors is an accelerometer.
 29. Theapparatus of claim 26 wherein the information indicates a change in thespeed of the vehicle both before and after detection of the collision.30. The apparatus of claim 26 wherein the sensors for monitoringproduction-related parameters includes a sensor for detecting a degreeof braking of the braking system.
 31. The apparatus of claim 26 whereinthe information includes one or more positions of the throttle leadingup to the detection of the collision.
 32. The apparatus of claim 26wherein the information includes the on/off status of the braking systemleading up to the detection of the collision.
 33. The apparatus of claim32 wherein the information includes one or more positions of thethrottle leading up to detection of the collision.
 34. The apparatus ofclaim 26 wherein the sensors for monitoring production-relatedparameters of the vehicle include a sensor for determining a state of aseat belt in the vehicle.
 35. A method for recording operation of avehicle, the method comprising: monitoring positions of a throttle foran engine for the vehicle and a load carried by the vehicle; detecting acollision of the vehicle; and recording one or more positions of thethrottle and a condition of the load preceding the detection of thecollision.
 36. The method of claim 35 including monitoring a status of abraking system of the vehicle and recording the status in response todetection of the collision.
 37. The method of claim 35 includingmonitoring a status of a seat belt and recording the status in responseto detection of the collision.
 38. The method of claim 35 includingmonitoring a ground speed of the vehicle and recording the ground speedin response to detection of the collision.